<div dir="ltr">According to my very limited understanding, luatex is generally slower than pdftex because the font loading is more involved [1,2,3,4]. In pdftex, compilation can be sped up by precompiling a preamble to a format, which loads much faster. To my understanding precompiled formats are not that useful in luatex due to mixing of tex- and lua-code. [5]<div><br></div><div>As I'm probably not the only one that writes many more short math-oriented notes than complete books, the startup speed of luatex is an issue. I resisted the switch from pdftex to luatex very long because of this.</div><div><br></div><div>How hard would it be to make a luatex compatible precompiled format? One that basically serialises the whole luatex state to a file and could re-use it? Would it speed up the compilation of short documents? Is there any plans or projects related to this?<br><div><br></div><div>Best regards and season's greetings,</div><div>thank you for the wonderful tools you have brought us!</div><div>Henrik Mannerström</div><div><br></div><div>[1] <a href="https://tex.stackexchange.com/questions/690903/format-dumping-using-lualatex-and-mylatexformat">https://tex.stackexchange.com/questions/690903/format-dumping-using-lualatex-and-mylatexformat</a></div><div>[2] <a href="https://tex.stackexchange.com/questions/114742/speeding-up-compilation-using-precompiled-preamble-with-luatex">https://tex.stackexchange.com/questions/114742/speeding-up-compilation-using-precompiled-preamble-with-luatex</a></div><div>[3] <a href="https://tex.stackexchange.com/questions/75118/why-does-it-take-lualatex-so-long-to-load-fonts-and-can-i-speed-it-up">https://tex.stackexchange.com/questions/75118/why-does-it-take-lualatex-so-long-to-load-fonts-and-can-i-speed-it-up</a></div><div>[4] <a href="https://tex.stackexchange.com/questions/234757/why-is-lualatex-so-slow-and-is-there-anything-i-can-do-about-it">https://tex.stackexchange.com/questions/234757/why-is-lualatex-so-slow-and-is-there-anything-i-can-do-about-it</a></div><div>[5] <a href="https://tex.stackexchange.com/questions/324559/guidelines-for-using-mylatexformat-with-luatex">https://tex.stackexchange.com/questions/324559/guidelines-for-using-mylatexformat-with-luatex</a></div></div></div>